Genetic Analysis And Gene Mapping Of A Lateral-rootless Mutant Lrl6-1 In Rice

Root system is an important organ for plants to absorb water and nutrients from soil, which enables plants to grow in good living conditions. Meanwhile, root system has machined mechanism to support plant bodies and synthesizes plant hormones. Strong root system play a decisive role for plant to maintain living activities and resist environmental stresses. Lateral roots are capable of increasing root surface area to absorb water on nutrients. Understanding of developmental mechanism of lateral roots will help us to breed varieties with higher efficiency of water and nutrient utilization.By screening a rice EMS-generated mutant library (Kasalath, indica), we isolated a mutant defective in lateral root, designated as lrl6-1.The phenotypic, physiological and genetic characterizations of lrl6-1 were investigated. The results are summarized as follows:1. The lateral roots (LR) of the lrl6-1 mutant seedlings grew shorter on the primaryroot and the number of LR was significantly less than the wild type (WT) during the growth period within twenty- eight days.2. Genetic analysis with reciprocal crosses between lrl6-1 mutant and wild-type plantsindicated that lrl6-1 possessed a recessive mutation.3. The LRL6-1 gene was mapped near RM26559及RM3428 on chromosome 11 bymap-based cloning.